At 2014 international CES in Las Vegas, Ford has presented its C-Max Solar Energi concept which uses solar power to directly charge the plug-in hybrid's battery pack. Rather than plugging in your C-Max Energi each time you stop, you park below a special solar concentrator with Fresnel circular lenses. This magnifies the sun's rays onto the roof of the car which is covered by solar panels. Relatively small roof-mounted solar array gathers enough light during a day's charging for a full battery top-up which is estimated to have the same total range as a conventional C-MAX energi with up to 1000km (626 miles), including up to 35 electric-only kilometers (21 miles).